Designed by Rietveld in 1934, this chair sees the normal legs-seatback sequence replaced by a single sheet of wood in an overturned Z shape.

It was also one of the first examples of a cantilevered seat. The dovetail joints, visible on the rear between the seat and the back show off the quality of Cassina carpentry. In addition to the version in natural cherry wood, the chair also comes in natural ash and in a coloured version with an open-pore finish to show off the wood vein, featuring primary colours (red, blue and yellow) and non-colours (black and white) for the horizontal parts and natural ash for the side sections.